Wire enameling die



May 3o, 1961 Filed May 19, 1958 P. J. ZERWES WIRE ENAMELING DIE 2 Sheets-Sheet l INVENTOR.

i da/ @mea 5% WML* 44 May 30, 1961 P. J. ZERWES WIRE ENAMELING DLE 2 Sheets-Sheet 2 Filed May 19, 1958 Y ,2,936,116 .WIRE ENAMELING DIE Paul I. Zerwes, Chicago, Illy., assignor to Chicago Magnet Wire Corporation, Chicago, Ill., a corporation of Illinois v f I i Filed May 19, 1958, Ser. No. 736,215 l14 claims. (ci. 11s-12s) 'Ihis invention relates generally to apparatus for applying a liquid coating or impregnant to lamentary material in a continuous process and more particularly, relates to an improved wire enameling die for use in such apparatus.

Although the invention is described in detail in connection with the application of insulative coatings to electrical conductors, such= as, Wire or cable (hereinafter referred to collectively as wire), it will be appreciated that the invention may be usefully employed for coating of filamentary materials of other than a metallic nature. For purposes of applying an insulative coating to such electrical conductors, enamel, varnish, lacquer or the like materials have been used which may be highly viscous. In referring to the invention as a wire enameling die the wordA enamel is intended to be generic in connotation as including all such insulative materials. Such coated wires have been widely used in electrical windings ory The apparatus used in such coating processes include generally a pay-off reel on 'which a continuous length of the bare wire is wound. The wire is unwoundfrom the reel for passage through a bath of the coating liquid and then, through a die structiure, the function of which is to remove excessive coating liquid to form a uniform coating around the wire.y Thereafter, the wire is passed through a heating chamber to dry and harden the liquidmaterial. This is called baking. The invention is concerned only with the die structure by means of which the uniform coating for the wire is achieved.

Die structures heretofore employed have been characterized by certain vdisadvantages in construction which have contributed to less than satisfactory operation therefor in such continuous coating processes. In particular, the speed and continuity of the process has been greatly hampered and rendered more expensive by reason of the use of such prior dies. A frequent occurrence in such processes is breaking ofthe continuous length of wire so that same is required to be re-threaded through the die in order thatrthe process may be continued. Rethreading of the wirevt-hrough such prior dies has been ditncult, cumbersome and time consuming with resultant increasein the costfof manu-facture. Another dificulty has been encountered in connection with the proper cleaning of such dies, namely, `removing undesirable accumulations of the coating liquidv so that the wire could be re-threadedtherethrough and traverse the die properly during subsequent `coating process, by reason of structural features whichdidjnotper-mit easy and convenient access to the interior areas of the die and cleaning of the uniform coating-forming aperture at one end of the die. In other 4typesof' ,die structures, portionsof the die had to be fs'preadfaj'ntrtl-in 'order to enable insertion of the wire thereinto 'and frequently, the die W-as ICC required to be replaced by reason by distortion which did not permit proper registry of the die parts after frequent re-threading procedures. Of course, resultant frequent replacement of such dies was reflected in increased cost of manufacture.

Accordingly, it is a principal object of the invention to provide a wire enameling die of the character described which is characterized by a construction therefor which successfully eliminates the disadvantages hereinabove enumerated.

An important object of the invention is to provide a wire enameling die of the character described which is comprised of at least a pair of cooperably associated die parts which are movable one relative the other between a first position which permits the wire to be inserted therein to a second position` which completes the die with the wire engaged through the coating-forming aperture of the die.

Another important object of the invention is to provide a wire enameling die of the character described comprised of a pair of die parts cooperably assembled to form the die, said parts being rotatable one relative the other and having cooperating entrance means for inserting the wire into the die and cooperating coating aperture forming means, said parts being rotatable one relative the other for separably rendering said entrance means and apertures Aforming means operable.

A primary object of the invention is to provide a wire enameling die of the character described comprised of a pair of hollow, cylindrical parts telescopically fitted one within the other, said parts being separable for purposes of removing undesirable accumulations of liquidI coating material speedily and handily, lwhenever necessary.

Another object of the invention is to provide a wire enameling die as described in which said parts have cooperating entrance means for inserting the wire thereinto, said entrance means being operative without requiring dissociation of the telescopically engaged cylindrical parts.

Another object of the invention is to provide a wire enameling die of the character described in which the die is assembled into operative condition by a predetermined series of movements of the said parts one relative the other wherein upon final adjustment of the parts, the wire automatically is properly seated in the coating-forming aperture thereof.

Another object of the invention is to provide a |Wire enameling die of the character described in which the die parts are concentrically arranged, each of said parts has an axially extending guide slot therein providing said cooperating entrance means for the Wire, said parts being rotatable one relative the other for disposingthe slots in registry one with the other to permit insertion of the wire therethrough into the die, s-aid slots thereafter required to be positioned in mis-registry position one relative the other in order yto render the die operative.

A further object of the invention is to provide a die structure as described in which the'said coating-forming aperture is provided in a transverse end wall structure of the die formed by a pair of cooperating end formations integral respectively with each of said cylindrical die parts.

Still another object of the invention is to provide an enameling die of the character described in which said die parts are capable of being telescopically tted one within the other and having surface portions thereof l juxtaposed at one end of the completed die along a plane of juncture substantially perpendicular to the longitudinal axis of the die, and said coating-forming aperture is located intermediate the ends of and lying upon said plane of juncture. K

Still another object of the invention is to provide a Patented May 30, 1961- wire enameling die as described which in a modified form thereof has said juxtaposed surface portions wedgingly ngaged to form a seal at the coating-forming end of the Still another object of the invention is to provide a wire enameling die in which in a modified form thereof includes a novel guide formation provided in one of said cylindrical parts for assisting in positioning of the wire for threading through the coating-forming aperture. A

The foregoing and other objects of the invention will become apparent, including the greater economy engendered by the construction of the wire enameling die which does not require replacement by reason of frequent distortion or clogging thereof as occasioned in prior art structures. Preferred embodimentsrof the invention have been described in detail in the specification and illustrated in the accompanying drawings from whence an understanding and appreciation of the principles of operation thereof will be garnered. Minor departures in the size, arrangement, proportions and construction of the parts of the invention are contemplated without departing from the scope or sacrificing any of the advantages of the invention.

In the drawings wherein the same characters of reference have been employed to identify the same or equivalent parts throughout the several figures thereof:

Fig. 1 is a diagrammatic view of apparatus for coating wire in a continuous process, the die structure embodying the invention shown in operative position for removing excessive liquid coating the wire passing therethrough.

Fig. 2 is 4a plan view of the wire enameling die embodying the invention and showing portions of wire entering and leaving the die. Y

Figs. 3 and 4 are end-on elevational views looking toward the right and left ends respectively of the die as showninFig. 2. v M

Fig. 5 is a plan view of the die in which the cooperating cylindrical parts thereof have the guide slots for the Wire in registry, said parts being partially retracted and rotated 180 one relative the other from their position in Fig. 2.

Fig. 6 is a sectional view taken along the line 6 6 of Fig. 2 and in the direction indicated.

Fig. 7 is a plan view of the die rotated through an angle of approximately 90 from the position thereof in Fig. 2.

Fig. 8 is a sectional view taken along the line 8+8 of Fig. 2 and in the direction indicated. Y

Fig. 9 is a plan view of the outer cylindrical part of the die and Figs. l and 11 are end-onnelevational views taken respectively of the left and right hand ends of said part as viewed in Fig. 9.

Fig. 12 is a plan view of the inner cylindrical part of the die and Figs. 13 and 14 are end-on views taken respectively from the left and right hand ends of the part as seen in Fig. 12. Y

Fig. 15 is a fragmentary plan view of a modified form of the die embodying the invention.

Fig. 16 is a sectional view taken on a horizontal plane through the die illustrated in Fig. 15.

Figs. 17 and 18 are fragmentary plan views of the inner and outer die parts respectively of the die of Fig. 15.

Fig. 19 is an end-on elevational view of another modified form of the invention.

Referring to Fig. 1 wherein a representative apparatus for coating filamentary material is illustrated diagrammatically, a continuous length of wire 20 is payed off reel 22 for passage over a guide roller 24 associated with the coating liquid bath 26 for applying the coating liquid 28. Upon emergence from the bath, wire 20 enters through an open end of the die structure which embodies the invention( designated by the reference character 30. The die 30 has been illustrated mounted in operative posi; tion on a wall of the bath by means of the clamping bracket 32 and fastening screw 33, however, it may be understood that other mounting means for the die 30 may be employed and that the die even may be operatively positioned upon structure apart from the bath 26. Upon traversing the die which has a coating-forrning `aperture at its opposite end facing toward the bath 26, the configuration of which matches the cross-sectional configuration desired for the coated wire and by means of which the uniform coating on the wire is achieved, the wire enters a heating or baking chamber 34. Upon egress from the heating chamber, the coated wire may be wound on reel- 36 or returned tothe bath forcontinued passes through the coating apparatus by means of suitable retum-conveyor means, not illustrated because irnmaterial to the hereininvention.` Y l The embodiment 30 of the invention is comprised of a pair of cooperating die parts or members 40 and 42 which may be formed of metal or other material suitably resistant to the coating liquid. 'In their assembled condition, members 40 and 42 are concentrically arranged with member 40 having membe 42 telescopically fitted therein.

Outer die member 40 comprises a sleeve or shell 44 of substantially uniform, circular cross-section open at one end 46 thereof, said end being knurled or scored on the exterior surface of the sleeve as seen at 48 for convenient handling of the member. At its opposite end the sleeve has an axially extending terminal formation 50 tapered toward its free extremity 52 along the inclined flattened exterior surface 53 of said terminal formation. Said sleeve may be formed to shape as by casting or be machined from cylindrical stock by milling or otherwise removing a right angle semi-cylindrical segment such as indicated by character 56 so that end face 54 of the sleeve lies in a plane normal to the longitudinal axis of the sleeve. There is defined a semi-circular opening 58 at said opposite end of the sleeve whose center of curvature is coincident with the longitudinal axis of the sleeve 44.

Referring to Fig. 5, the formation 50 may be seen to have a flat inner face or surface 60 which has a generally triangular inner configuration caused by a semicylindrical recess 62 formed therein, the plane of said face 60 being perpendicular to the end face 54 and coincident with the longitudinal axis of the sleeve 44. Thus, extremity 52 of formation 50 may be seen to be linear and parallel with end face 54 and equal in length to the outside diameter of said sleeve. A semi-cylindrical axially extending groove 63 is cut in said surface 60 which communicates at its ends with the extremity 52 and the interior of the sleeve. The axis of groove 63 is coincident with the longitudinal axis of sleeve 44. A continuous slot 64 extends longitudinally from end face 54 to open end 46 and as seen in Fig. 14, the slot 64 is formed in the semi-cylindrical wall 65 of the sleeve which defines the openingg'SS and is aligned opposite groove 63. The slot 64 is in the nature of a guide for introducing a wire therethrough in a radially inward movement for seating in the goove 63. v

Inner `'die member 42 also is comprised of a hollow sleeve such as 70, of uniform circular cross-section and havingran outside diameter permitting sliding, telescopic engagement thereof on the interior of member Ihe sleeve has an open end 72 and an exteriorly knurled or scored annular end band 74 which may be separated from the remainder of the exterior surface ofthe sleeve by neck 76, and can be made by employing well-known metal working techniques. At its opposite end, the sleeve 70 has face 82 normal to the axis of the sleeve and a semicircular opening 84. The axes of end face 82 and 'opening 84 coincide with the axis of said sleeve. Extending axially outward of said end face 82 is a terminal formatin 86 tapered toward its extremity 88 along' the inclined flattened exterior surface thereof.

The formation86 also has a hat uinner face r surface 94 theplane of which is pe'zrfueiitlc'ula'i` to end face v82` and coincident with the axis 'of the 'member '42. Extremity i likewise' is linear land parallel to end face 82 with the length ythereof equal to the outside diameter of said member. A'semi-cylindrical elongate groove 96 is formed in said face 94 which extends from extremity 88 to communicate at its opposite end with the interior of sleeve 70, the axis of the groove lying on the longitudinal axis of member 42. In the embodiment illustrated, grooves 63 and 96 are identical and selected so that when arranged facing one toward the other, they will form a circular coating-forming aperture which matches the cross-sectional conguration desired for the coated Wire passed therethrough. It will 'be apparent that the size of the respective grooves is therefore selective depending upon the desired diameter for the coated wire. A longitudinally extending slot 98 extends from end face 82 to the opposite end 72 and, as seen in Fig. 11, is formed in the semi-cylindrical wall 99 aligned opposite groove 96.

As illustrated in Figs. 9 and l2, the circumferential wall of member 40 is provided with a recess 100, there being a second such recess on the dametrically opposite surface of the Wall. Likewise, the member 42 is provided with a pair of diametrically opposed indentations, such as 101 in the vannular exterior surface thereof. In the completed form of the die, each recess 100 is aligned or in registry with a said indentation .101 to provide a concave seat for the end 102 of the screw 33 (Fig. 2) when the die is mounted in its operative position seen in Fig 1. The end 102 is engaged against the indentation 101 through recess 100 and assists not only in the mounting of the die, but also in preventing axial separation of the members 40 and 42 during the coating process. A locking pin or slug 102' may be provided on the bracket also. The invention contemplates, as well, other means being employed for mounting the die in operative position during the coating process although the means described are effective and advantageous.

Referring to Fig. 5, the parts 40 and 42 are shown in a partial condition of assembly in which part y42 has been telescopically fitted into the part 4'0 and the longitudinally extending slots 64 and `98 are in precise registry. In this relative position of the die members, the flat face 60 of formation 50 and the at face 94 of formation 86 will be parallel and facing in the same direction. This condition Will always obtain when the die members are concentrically arranged and the slots 96 and 98 are in precise registry one with the other. However, for purposes of inserting die member 42 in the die member 40, such registry condition of the slots is not required. Continued axial movement of the member 42 to the right as viewed in Fig. 5 will dispose the extremity 88 of formation 86 into engagement with the transversely extending inner end face of formation 50 indicated by the line 103 in Fig. 5. In this position, the grooves 63 and 96 will be aligned one Vwith the other and the slots 64 and 98. It may further be noted that in ythis relative arrangement of the die members, the formation 86 will be laterally spaced from the formation 56 along the longitudinal axes of the concentrically arranged members.

The wire 20;ma`y not be passed radially inward through the aligned slots 64 and 98 into the interior of member 42, it being immaterial at this point whether or not the wire is seated inthe laligned grooves 63 and 96. The axial length of member 42vis greater than that of the member 40 so that the annular band end 74 of member 42 protrudes outwardly from the open end 46 of the member 40 to provide for convenient handling of the die members. The members may now be rotated one relative the other through approximately 180 from their relative position shown in Fig. 5 so that face 94 is parallel with and facing in a direction opposite that toward which the face 60 is directed. This relative movement will align the formation 86 opposite the semicircular opening 58 in sleeve 44. The die member 42 may now be slid yaxially to pass formation 86 through 6 the :member 42frelative member 40 is-limitedby cooperative'fstop means providedon the interior of the die, saidly stop means 'comprising the lend face '82 abutting formation 50 as'indicated at 104 in Fig. 8.' It will be appreciated thatl saidfstop means may vary in form to a In the completed die 30,` inner faces 60 andv 94 of the p respective terminal formations are juxtaposed as indicated by the lineV in Fig. 3 and the extremities 52 and 88 'are substantially flush with the grooves 63 and 96 facing one another to form a coating-forming aperture indicated at 106 lying on the line 105 with its center coincident with the longitudinal axis of the die 30. Thus, the terminal formations 50 yand `86 cooperate to provide said aperture 106 in one end 108 (Fig. 2.) constituting the uniform coating-forming end which is imperforate except for aperture 106 by reason ofthe convergent Asurfaces 53 and 90 of said terminal formations.

In operation, the wire 20 passes through the aperture 106 whose diameter is selected to match the outside diameter of the coated'wire, whereupon excessive coating liquid is removed. Although the aperture 106 has been illustrated as being formed upon mating arrangement of the pair of grooves 63 and 98, it will be apparent that the same results may be 4achieved by providing the desired aperture in only one-of the' formations 50 or 86.

Should the wire20 break during the coating process, l cleaning of the die yand re-th-reading of the wire is a sembled in the manner described automatically seating the wire in the aperture 106.

A modified form of the invention is illustrated in Figs. 15 through 18 which in the completed form thereof is designated 110. The die 110 is substantially identical to the die 30 except for modifications in the terminal formations 1112 and 114 of the respective die members 116 and 118. It may be seen that member 116 comprises the inner die member and member 118 comprises the outer one, and terminal formations 112 and 114 correspond to the formations 86 and 50 respectively. However the flat inner surface 120 of member 116 describes a plane which is not perpendicular to end face 122 of member 116 as in the case of die member 42 and same is true of inner planar surface 124 relative end face 126 of the member 118. Thus, the inner surfaces 120 and 124 meet along a planar juncture 128 (Fig. l5) which is disposed at an angle relative the end faces 122 and 126 and the longitudinal axis of the die 110. The result is that upon moving the formation 112 through semi-circular opening defined by end face 126 of member 118, the surfaces 120 and 124 will be slightly wedged together and thereby form a very tight seal at the end 130 of the die comprising the uniform coating-forming end of the die. Such wedging engagement will resist displacement of the die members one relative the other to a small extent.

Referring to Fig. 19, a second modified form of the invention is designated generally 132. The die 132 is substantially identical in structure as the preceding dies described except for the inner surfaces of the die aperture forming terminal formations of the outer die member 134 and inner die member 136 respectively. The terminal formations of said die member meet along a V-shaped line of juncture indicated at 138, the apex of which has the uniform coating-forming aperture 140 thereat. Thus, the terminal formation of the outer die member 134 has opening 58. The extent of such sliding movement of u a V-shaped trough formation opening toward the longiwire seated in the groovesu63 tudinal slots ofthe die members when in registry condition which assist in sliding the wire into position for threading thereof through the coating-forming aperture 140 when the die members 134 and 136 are assembled. However, as previously explained, such a trough or guide formation is not essential since the wire will automatically be threaded through the uniform coating-forming aperture when the die members are in nal condition of assembly.

It will thus be seen that the invention, in its broadest application, provides for a die structure formed of at least two cooperating die parts or members. Said members have means cooperable to provide a wire coating aperture through which the wire is passed to form a uniform coating. Said members also have cooperating entrance means for insertion of the wire thereinto, said members being rotatable one relative the other to render the entrance means operable in one position of the members and out of registry or inoperable in a second position thereof. Where the invention is' embodied in the cylindrical die members described and illustrated, provision has been made for both rotatable and sliding movement of the die members one relative the other for this purpose.

It is believed the invention has been described in suincient detail to enable the skilled artisan to understand and practice the same. Variations are believed possible, such as in the type of material used, external configuration and the like of the die members without circumventing the invention. The invention has been particularly pointed out in the claims hereto appended, it being intended that the language of the claims be construed broadly commensurate with the improvements in the arts and sciences engendered thereby.

What it is desired to secure by Letters Patent of the United States is:

1. A wire enameling die comprising, a pair of telescopically assembled hollow sleeve members eachv open at one end thereof, each member having a terminal formation at its opposite end cooperable one with the other to form a uniform coating aperture, said sleeve members having radially extending lguide means cooperable to permit insertion of a wire therethrough for seating in said aperture, said members being rotatable one relative the other between a nrst position in which the guide means are operably arranged to permit such insertion and a second position in which said guide means are rendered inoperable.

2. A wire enameling die as described in claim 1 in which said terminal formations are axially displaced one relative the other in said rst position.

3. A wire enameling die as described in claim 1 in which said guide me'ans comprise elongate slots in circumferential walls of said sleeve members.

4. A wire enameling die as described in claim l in which said aperture has the center thereof coincident with the longitudinal axis of the die.

5. A wire enameling die as described in claim 1 in which said terminal formations have facing inner surfaces in said second position and s'aid surfaces have grooves therein cooperable to form the aperture.

6. A die as described in claim l in which said members have means for operably mounting the die comprising, a recess and seat formation formed in said second position adapted t receive a locking pin in position to prevent axial separation of the members.

7. A wire enameling die as described in claim l in which said terminal formations have facing inner surfaces in said second position and the aperture is located in at least one of said surfaces.V

8. A die as described in claim 7 in which said surfaces are wedgingly engaged together in said seeond position.

9. A wire enameling die as described in claim l in which the outer member has a shaped opening in its opposite end and the terminal formation of the inner member is slidably engaged through said opening in said second position.

l0. A die as described in claim 9 in which said members have cooperating stop means for limiting the extent of said dsliding movement.

1l. A wire enameling die comprising, a pair of tele` scopica'lly assembled cylindrical members providing an inlet opening into the inner member from one end and a coating-forming aperture at the opposite end of the die for passing a wire through said aperture in a continuous coating process, said members being rotatable and axially displaceable one relative the other in said assembly, said members having cooperating entrance means for introducing a wire into the die in a' radially inward movement, said members being movable one relative the other be tween a first position in which said entrance means are rendered operable and a second position in which said entrance means are rendered inoperable, said aperture being provided only in said second position of the members, said members having cooperating terminal formations forming said aperture in said second position.

12. A die as described in claim 1l in which said aperture is coincident with the longitudinal axis of the members.

13. A die as described in claim 1l in which the outer member has an opening in one end thereof through which the terminal formation of the inner member is slidably engaged in said second position, and there are stop means limiting the extent of said sliding movement.

14. A coating die for lamentary material comprising an assemblage of parts providing an opening at one end and a coating-forming aperture at the opposite end of the die for accommodating a moving wire passed axially through the die, said parts each comprising a hollow, cylindrical sleeve open at one end thereof and having a shaped terminal formation at its opposite end, said terminal formations cooperable to form said aperture in the assembled condition of the die parts, each part having a slot in the circumferential wall thereof extending the entire length of the part, said parts being telescoped one within the other with said formations positioned to form said aperture, and being displaceable one relative the other along the axis of the die and rotatable one relative the other to permit alignment of the slots for insertion of a Wire into the inner part through the circumferential walls of both parts, said parts thereafter adapted to be reassembled with sequential rotary and axial movement thereof one relative the other to seat the wire in said aperture.

References Cited in the nle of this patent UNITED STATES PATENTS 1,230,714 Houston June 19, 1917 1,811,505 Kennedy June 23, 1931 2,347,392 Bouger t Apr. 25, 1944 2,351,110 Davidson et al. June 13, 1944 

